Throttling pump



Patented Jan. 16, 1940 v UNITED STATES PATENT OFFICE 3 Claims.

This invention relates particularly to fuel pumps for Diesel engines.

Special objects of the invention are to provide an improved throttlingconstruction, which will be incorporated with and form an actual part ofthe pump and which will be of simple, practical design and accurate andreliable in operation.

These and other desirable objects are attained by the novel features ofconstruction, combinations and relations of parts hereinafter described,illustrated in the accompanying drawing and broadly covered in theclaims.

The drawing shows one practical embodiment of the invention and it is tobe understood that the structure may be modified and changed as regardsthis particular illustration, all within the true intent and broad scopeof the invention.

Fig. 1 is a broken sectional view of a throttling pump embodyingfeatures of the invention.

Figs. 2 and 3 are diagrammatic views illustrating other positions of theparts.

Fig. 4 is a broken side elevation with parts appearing in section as online 44 of Fig. 1.

In the construction illustrated, the cooperating pumping elementsconsist of a stationary piston or head member 5, and a movable cylinder6, reciprocating over said head member. The reciprocation of thecylinder 6, is effected from a cam l, on shaft 8, operating against acam roll 9, on one end of the pivoted rocker I6, having a fork II, atthe opposite end bearing on the head l2, of the cylinder, against thetension of spring l3, interposed between the outstanding flange M,

of said head and the shoulder l5, about the base of the piston.

In a multi-cylinder pump such as illustrated, the oil may be suppliedfrom a suitable manifold I6, to branches l1, having suitable checkvalves l8, therein. These branches to the individual pumps may open topassages I9, in the bases of the stationary pump pistons.

The stationary pump element 5, is tubular in form to provide a bore orchamber 26, for receiving the throttling sleeve 2|. The latter projectsthrough an opening 22 in the head l2 of the reciprocating pump memberand, for adjustment purposes is shown as having a transversely slottedhead or yoke 23, receiving the eccentric 24 on the control rock shaft25.

The throttle sleeve is shown as ported in its upper portion at 26, toclear the end of piston member 5, and as ported in its lower portion at21, to clear the head of the movable cylinder, when the sleeve iswithdrawn as in Fig. 3 and as channeled in the side at 26c between ports26 and 21. The throttle shaft 25 may be equipped with a suitable leveror handle for rotating the same to similarly set the throttles for theseveral pumps in different desired positions.

The chamber orbore 26, in the stationary pump 5 member is shown asextended as a passage 28, from which pipe 29, may be extended to theinjection nozzle of the engine cylinder.

With the throttle set as in Fig. 1, substantially the full displacementof the pump will be utilized, 10 the outstroke of the cylinder causing afull charge of the oil to be drawn through the lower sleeve ports 2?,into the space between the end of the stationary member 5 and the head[2 of the movable cylinder 6. On the instroke, this 15 full charge willbe forced to the atomizer or injection nozzle of the engine cylinder upto the instant of pressure relief by the opening of ports 21, Fig. 2.

By withdrawing the throttle sleeve as in Fig. 20 3, the upper ports 26,can be brought into communication with the pumping space or chamber 36,and the lower ports 21, can be carried outside the range of movement ofthe cylinder head l2, with the, result that oil taken into the pump 25chamber through ports 26, will simply be discharged through ports 21,into the enclosing chamber 3|, from which such oil may be led throughpiping 32, back to the source of supply. Adjustments between theseextreme positions will vary the volume of oil which is thus released andconsequently the amount of oil that will be actually pumped to theengine cylinder. This throttling or bypassing effect is obtained rightat the pump, the source of pressure, without shifting or varying thepump parts and with a simple rugged construction, free of anycomplicated or delicate parts liable to get out of order.

What is claimed is:

l. A throttling pump comprising companion relatively movable cylinderand piston pumping elements and a throttling sleeve member extendingthrough the end of said cylinder and piston elements and ported tocooperate with both pumping elements and shiftable to vary the pumpingeffect of such elements and inlet and outlet connections for said pumpstructure the porting of said throttling sleeve including a port locatedand constructed to provide continuous communication between the interiorof the sleeve and space between said sleeve and surrounding pumpingcylinder and a port located and constructed to provide in alternatepositions of the sleeve communication between the interior of the sleeveand said surrounding space within the cylinder 55 or communicationbetween the interior of the sleeve and space outside both the sleeve andthe cylinder element.

2. In combination with a stationary tubular pumping member, a movablepumping cylinder operating over said member and having a closed head atthe outer end of the same, a throttle sleeve slidable in said member andprojecting out through the head of said pumping cylinder, said throttlesleeve having a port to clear the end of the tubular member in which itis located and a port to open outside the head of the movable cylinderwhen said throttle sleeve is partly withdrawn from said tubular pumpingmember and inlet and outlet connections for said pump structure, saidfirst sleeve port being located and constructed to provide continuouscommunication between the interior of the sleeve and space between theoutside of the sleeve and the surrounding pumping cylinder and saidsecond mentioned port being located and constructed to providecommunication either between the interior of the sleeve and saidsurrounding space within the pumping cylinder or between the interior ofthe sleeve and exterior of the pumping cylinder.

3. A throttling pump, comprising a relatively stationary tubular pistonhaving fluid inlet and outlet, a pumping cylinder operating over saidstationary tubular piston and having a head at the outer end of thesame, a throttling sleeve extending through the head of said slidingcylinder and having a sliding fit in the bore of the stationary tubularpiston, said throttling sleeve being ported for cooperation with the endof the stationary tubular piston and the head of the cylinderreciprocating over the same and located and constructed to providecontinuous communication between the space within said throttling sleeveand the space between said sleeve and surrounding pumping cylinder andto provide communication between the interior of the sleeve and saidsurrounding space or the interior of said sleeve and space outside saidsleeve and pumping cylinder, means for operating said cylinder and meansfor variably positioning the throttling sleeve with respect to the endof the stationary tubular piston and the head of the movable pumpingcylinder.

GEORGE A. GILLEN.

